Deep-throating is a sexual act in which a person takes a partner's entire erect penis deep into the mouth and throat. The practice is a type of fellatio where the receptive partner (the one whose mouth receives the penis) is in control, while deep throat penetration by an actively thrusting partner is called irrumatio; both are a form of oral sex.[1][2] For deep-throating, the penis has to be long enough so that it can reach the back of the recipient's throat.[1]

Deep-throating can be difficult, due to the natural gag reflex triggered when the soft palate is touched.[3][4] Different people have different sensitivities to the reflex, and with practice, some people learn to suppress it. Deep-throating leads to an entirely different kind of oral stimulation in comparison to regular fellatio: the tongue is immobilized during deep-throating and sucking becomes impossible;[5] the glans penis can be intensely stimulated by the tightness of the pharynx.

There are several positions that are well suited for performing deep throat. Relaxation of the throat muscles is the most important aspect of positioning.

One common position is to align the mouth and throat into a straight line (like a sword swallower), but many different positions are possible.

"Over-the-edge" is a common position for deep-throating. In this position, the receptive partner lies back and hangs his or her head off the edge of a bed or similar piece of furniture, and the insertive partner stands or kneels in front of the face, lining up his penis at mouth level.

Another common position used for deep-throating involves the insertive partner sitting on the receptive partner's chest, with his penis in front of the face.

^Freud, Sigmund (1916). Leonardo da Vinci: A PSYCHOSEXUAL STUDY OF AN INFANTILE REMINISCENCE. New York: MOFFAT YARD & COMPANY. p. 39. Retrieved January 7, 2012. The situation contained in the phantasy, that a vulture opened the mouth of the child and forcefully belabored it with its tail, corresponds to the idea of fellatio, a sexual act in which the member is placed into the mouth of the woman.